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  2. Local standard of rest - Wikipedia

    en.wikipedia.org/wiki/Local_standard_of_rest

    In astronomy, the local standard of rest or LSR is a reference frame which follows the mean motion of material in the Milky Way in the neighborhood of the Sun (stars in radius 100 pc from the Sun), [1] on average sharing the same velocity around the Milky Way as the Sun. [2] The path of this material is not precisely circular. [3] The Sun ...

  3. Proper motion - Wikipedia

    en.wikipedia.org/wiki/Proper_motion

    This motion is caused by the movement of the stars relative to the Sun and Solar System. The Sun travels in a nearly circular orbit (the solar circle ) about the center of the galaxy at a speed of about 220 km/s at a radius of 8,000 parsecs (26,000 ly) from Sagittarius A* [ 5 ] [ 6 ] which can be taken as the rate of rotation of the Milky Way ...

  4. Peculiar velocity - Wikipedia

    en.wikipedia.org/wiki/Peculiar_velocity

    In galactic astronomy, peculiar motion refers to the motion of an object (usually a star) relative to a Galactic rest frame. Local objects are commonly examined as to their vectors of position angle and radial velocity. These can be combined through vector addition to state the object's motion relative to the Sun.

  5. Speed - Wikipedia

    en.wikipedia.org/wiki/Speed

    Average orbital speed of planet Earth around the Sun: 29 783: 97 713: 107 218: 66 623: The fastest recorded speed of the Helios probes: 70,220: 230,381: 252,792: 157,078: Recognized as the fastest speed achieved by a man-made spacecraft, achieved in solar orbit. Orbital speed of the Sun relative to the center of the galaxy: 251 000: 823 000: ...

  6. Orbital speed - Wikipedia

    en.wikipedia.org/wiki/Orbital_speed

    In gravitationally bound systems, the orbital speed of an astronomical body or object (e.g. planet, moon, artificial satellite, spacecraft, or star) is the speed at which it orbits around either the barycenter (the combined center of mass) or, if one body is much more massive than the other bodies of the system combined, its speed relative to the center of mass of the most massive body.

  7. Sun - Wikipedia

    en.wikipedia.org/wiki/Sun

    The Sun, taking along the whole Solar System, orbits the galaxy's center of mass at an average speed of 230 km/s (828,000 km/h) or 143 mi/s (514,000 mph), [167] taking about 220–250 million Earth years to complete a revolution (a Galactic year), [168] having done so about 20 times since the Sun's formation.

  8. Retrograde and prograde motion - Wikipedia

    en.wikipedia.org/wiki/Retrograde_and_prograde_motion

    Meteoroids in a retrograde orbit around the Sun hit the Earth with a faster relative speed than prograde meteoroids and tend to burn up in the atmosphere and are more likely to hit the side of the Earth facing away from the Sun (i.e. at night) whereas the prograde meteoroids have slower closing speeds and more often land as meteorites and tend ...

  9. Position of the Sun - Wikipedia

    en.wikipedia.org/wiki/Position_of_the_Sun

    Thus 4 minutes (more precisely 3 minutes, 56 seconds), in the equation of time, are represented by the same distance as 1° in the declination, since Earth rotates at a mean speed of 1° every 4 minutes, relative to the Sun. An analemma is drawn as it would be seen in the sky by an observer looking upward.